cachefsd

- CacheFS daemon

Synopsis

/usr/lib/fs/cachefs/cachefsd

Description

The cachefsd server implements features of the cache filesystem (CacheFS). It is
invoked at boot time and run if the / (root) and /usr
filesystems are being cached. If /usr is being cached, cachefsd is invoked by
inetd(1M) from inetd.conf(4). At run time, cachefsd is invoked by the inetd mechanism
in response to an RPC request from a user command such as
mount_cachefs(1M).

The cachefsd server supports the “disconnected mode” of CacheFS. In this mode,
a user can continue to read and, depending on the option selected,
write to files in a cached filesystem when the NFS server for
the cached files is not available.

The cachefsd daemon performs the following functions in support of the CacheFS:

Implements the connection policy. The daemon determines whether the NFS server backing the cache is connected or disconnected from the cache, or is in transition from the connected or disconnected states.

Implements “log rolling,” wherein the daemon monitors a disconnected NFS server for reconnection. After such a server returns to a connected state, cachefsd rolls any local changes to cached files (kept in a log) back to the server.

Manages “packing,” wherein cachefsd makes a best effort to ensure that files in a user-specified list are available in the cache in disconnected mode.

Supports user interfaces by supplying statistics, reporting conflicts between the cache and the back filesystem, and supporting a list of files for packing.

The running of cachefsd is required for the disconnected mode of CacheFS.